Four processes were needed for the
spontaneous origin of life on Earth:
1. Non-living synthesis of simple organic molecules
2. Assembly of these molecules into polymers
3. Origin of self replicating molecules that made
inheritance possible
4. Packaging of these molecules into membranes with
an internal chemistry different from their
surroundings
Assembly of these molecules into polymers
4 hypothesized locations:
•
Ocean-land interface hypothesis
•
Under
•
Clay hypothesis
•
Hydrothermal vent hypothesis
hypothesis
Ocean-Land Interface Hypothesis
• Early oceans carried simple organic
molecules
• The porous surfaces of shoreline minerals
helped organize such building blocks into
polymers.
Under Ice Hypothesis
Some scientists calculate that at one point,
the top 300 meters of the ocean were
frozen over.
• Ice provided a protective shield from UV light
(which destroys organic compounds)
• Organic compounds are more stable in colder
temperatures and could combine in a lattice of ice.
Hydrothermal
Vent Hypothesis
• Release hot gaseous
substances which may
fuel polymerization
• Today, they are
surrounded by thriving
ecosystems
VIDEO
Hydrothermal Vent Hypothesis
Clay Hypothesis
Clay contains iron and zinc atoms which can
serve as inorganic catalysts for polypeptide
formation
Clay collects energy from radioactive decay and
discharges it if temperature or humidity
changes; could have been source of energy for
polymerization to take place
VIDEO